<template>
  <ul>
    <li :style="{opacity}">欢迎学习Vue</li>
    <li>news001<input type="text"></li>
    <li>news002<input type="text"></li>
    <li>news003<input type="text"></li>
  </ul>
</template>

<script>
export default {
  name: "News",
  data(){
    return{
      opacity: 1
    }
  },
  // beforeDestroy() {
  //   console.log('被销毁')
  //   clearInterval(this.timer)
  // },
  // mounted() {
  //   this.timer = setInterval(()=>{
  //     this.opacity -= 0.01
  //     if (this.opacity <= 0)this.opacity = 1
  //   },16)
  // }
  //激活调用
  activated() {
      this.timer = setInterval(()=>{
        this.opacity -= 0.01
        if (this.opacity <= 0)this.opacity = 1
      },16)
  },
  //切走失活
  deactivated() {
      console.log('被销毁')
      clearInterval(this.timer)
  }
}
</script>

<style scoped>

</style>